Always be nice, and cool. That's the motto around here. But sometimes you just want to make someone wildly uncomfortable. Or maybe you want to avoid social nightmare! Either way, here is some sacred social media advice. Heed or perish.

It's customary, when courting a potential sexual partner or vetting an employee, to go through their Facebook profile. And of course the best part of any profile is the tagged pictures, that constellation of arms-around-each-other, dorm vignettes, raised cups, and dour weddings. You can get a piercing look into the soul of modern man by seeing how lame he was in 2008, or how much weight he's gained since '11. Most of us are content with a few dozen photos—tap that right arrow on your keyboard, faster, faster, keeping pace with your heart. But that might not be enough.

You might end up speeding through time and space, back years, back to primordial Facebook, indigenous rock drilled with clicks. What a butt. Your hair! You had a cool backpack. And then you reach it.

The first picture. The first tag. It's usually unflattering, and the subject doesn't resemble the human you now know. Depending on what generation we're talking about, it could be a prom picture. Gosh.

But do not.
Under any circumstances.
Like that photo.

Don't click like.

Don't like the first photo. If you do, you have broadcast to perhaps thousands of mutual friends: Hello, I just scrolled through every single one of this acquaintance's pictures.

And that's a little weird! It'll show up on news feeds far and wide, causing people to wonder why a picture from 2006 has resurfaced. And then the subject in question will see that you liked it, and wonder why you're browsing photos of Lauren from 2006, and you'll be exposed as the creepy creep criminal you are. So don't do it. Just save a copy of the photo to a folder on your computer instead, where you can admire it as much as you want in a creepy little vacuum.

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